 | Acta Crystallographica Section F Acta Crystallographica Section F STRUCTURAL BIOLOGY COMMUNICATIONS |
journal menu
![[Figure 1]](fw5149fig1mag.jpg)
|
|
Figure 1
Flap migration and double-flap generation. The preferred substrate of FEN1/XPG-family nucleases is a double-flap DNA. Because single-stranded flap DNA is complementary to the template region, the 3′-end of the upstream strand and the 5′-end of the downstream strand form various flap structures following displacement synthesis by pol δ. During the transient flap-migration equilibration, FEN1 specifically recognizes the double-flap structure containing 5′-flap nucleotides with a one-nucleotide 3′-flap. A displaced 5′-flap DNA (red) was produced by DNA polymerase from the upstream strand. The flap is capable of migrating back and forth and forms various flap structures based on sequence complementarity between the template (black) and the upstream/downstream (blue) strands. FEN1 removes the 5′-flap by cleaving the double-flap substrate with one-nucleotide 3′-flap after the first base pair preceding the 5′-flap DNA to generate a nicked DNA product for the next DNA-ligase reaction. |
![[Figure 1]](fw5149fig1.jpg)
| STRUCTURAL BIOLOGY COMMUNICATIONS |
ISSN: 2053-230X
